TononixOS/ubports_kernel_google_msm
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

ext4: protect group inode free counting with group lock

Browse Source 
Patch from Ken that can solve fsstress failing issue
commit b9fa7bb8ff207eeb27d2e0ed45b8c3acf1a7af8c
Author: Tao Ma <boyu.mt@taobao.com>
Date:   Mon May 28 18:20:59 2012 -0400

    ext4: protect group inode free counting with group lock

    Now when we set the group inode free count, we don't have a proper
    group lock so that multiple threads may decrease the inode free
    count at the same time. And e2fsck will complain something like:

    Free inodes count wrong for group #1 (1, counted=0).
    Fix? no

    Free inodes count wrong for group #2 (3, counted=0).
    Fix? no

    Directories count wrong for group #2 (780, counted=779).
    Fix? no

    Free inodes count wrong for group #3 (2272, counted=2273).
    Fix? no

    So this patch try to protect it with the ext4_lock_group.

    btw, it is found by xfstests test case 269 and the volume is
    mkfsed with the parameter
    "-O ^resize_inode,^uninit_bg,extent,meta_bg,flex_bg,ext_attr"
    and I have run it 100 times and the error in e2fsck doesn't
    show up again.

Change-Id: Iba773843728759e1d64d4ff57765288eb5977665
Reviewed-on: http://mcrd1-5.corpnet.asus/code-review/master/67871
Reviewed-by: Lin Johnny1 <Johnny1_Lin@asus.com>
Tested-by: Lin Johnny1 <Johnny1_Lin@asus.com>
Reviewed-by: Sam hblee <Sam_hblee@asus.com>
This commit is contained in:
johnny1_lin
2013-01-15 10:14:01 +08:00
committed by Iliyan Malchev
parent e1ef9cc1d9
commit 3db674a036
1 changed files with 4 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
fs/ext4/ialloc.c
View File

@@ -772,7 +772,10 @@ got:
ext4_itable_unused_set(sb, gdp,
(EXT4_INODES_PER_GROUP(sb) - ino));
up_read(&grp->alloc_sem);
} else {
ext4_lock_group(sb, group);
}
ext4_free_inodes_set(sb, gdp, ext4_free_inodes_count(sb, gdp) - 1);
if (S_ISDIR(mode)) {
ext4_used_dirs_set(sb, gdp, ext4_used_dirs_count(sb, gdp) + 1);
@@ -784,8 +787,8 @@ got:
}
if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
ext4_unlock_group(sb, group);
}
ext4_unlock_group(sb, group);
BUFFER_TRACE(inode_bitmap_bh, "call ext4_handle_dirty_metadata");
err = ext4_handle_dirty_metadata(handle, NULL, inode_bitmap_bh);